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R60/6 Cold starting

wasserwolf

New member
Ok Guys, I need the benefit of some members with air head experience with respect to starting my R60/6. I have owned this for a year and it is my first airhead. I have nothing to compare my starting routine with and would like some experienced guys to chime in.

History First : Bike has new pistons/refurbished heads/rebuilt carbs. Runs great after it warms up.

My starting procedure:
Open the fuel lines, push down on the carb tickler, crack the throttle a tiny bit, hit the starter 6-8 times (with 30-40sec rests in between) until the engine catches. It starts with a very weak sounding thump/thump. During this initial period, the bike shakes. It takes about 5-8 minutes of warming up before I can apply any throttle and raise the RPM over idle. I close the tickler at about 3 minutes after it starts. The colder the morning temp, the longer it takes for the engine to catch. When I can finally twist the throttle and raise the RPM, I can pull away and begin to ride. I want to know if my starting ritual is normal for an old air head or do I have something not set quite right.

Thanks for any comments.
 
When was the last time you adjusted the carb idle?............Have you synced the carbs?...........What RPM is the machine running warmed up......cold????
 
I'd go with checking carb sync. The process isn't rocket surgery but you need to fail a bunch of times before the whole adventure makes sense to you.

Before I got crazy with the "what if's", I would change the plugs. Just cause they are new doesn't make them good. The first rule of thumb with a gas engine that is tough to start is change the plugs. It applies to everything from the chainsaw to the family car.
 
When was the last time you adjusted the carb idle?............Have you synced the carbs?...........What RPM is the machine running warmed up......cold????

Adjusted the carb idle last fall before putting it up for the winter. Carbs were synced last summer. RPM bobs between 900-1000 on the tach when warm , it just puts along at a very consistent rate. When its cold the tach is 500.
 
I'd go with checking carb sync. The process isn't rocket surgery but you need to fail a bunch of times before the whole adventure makes sense to you.

Before I got crazy with the "what if's", I would change the plugs. Just cause they are new doesn't make them good. The first rule of thumb with a gas engine that is tough to start is change the plugs. It applies to everything from the chainsaw to the family car.

Just replaced the plugs yesterday and had the same starting procedure. Old plugs had a slight carbon deposit but not too bad, overall they looked good, no oil deposits or melted electrode.
 
Have you checked the float level????...........Something says that it is starving for fuel............If when barely started, have you pulled plug wires to identify which side it is on???.........Should "chug" like it is doing if and when a plug wire is pulled and running on one cylinder. At least that way you would KNOW which cylinder to work on........God bless....Dennis
 
I'm not that familiar with the post 1970 "ticklers". The R60/6 should have slide carbs. Are the ticklers similar to the button you push down to literally flood the carb as was the case with the /2 slide carbs? If so, these are only used sparingly in order to get the mixture rich enough to start. They aren't left down for a long period of time.

If not the above, never mind! :wave
 
It would help to know the year. I believe the 1974 models had "ticklers". 1975 and 76 have an enrichment circuit.
This is assuming you have the stock carburetors.

The first thing I would do is a complete tune up.
Adjust the valves, check the point gap (replace them if they of unknown age and mileage, unless you are certain they are good)
You said you already replaced the plugs. Next check the caps and wires they do fail.
check your air filter, replace if dirty.
Check the ignition timing.
Then after these steps go for a 20 mile ride and adjust your carb, air mixture, idle speed and cable synch. work quickly or park your bike in front of one or two box fans so it doesn't over heat.

I own a 1975 R60/6. In my experience, it wants to start and run. I have had it for 40,000 miles. Mine has the "choke lever" on the claim shell. (this is really an enrichment circuit, I believe). Starting procedure when cold is push the lever about 3/4 of the way down, turn the key on, push the starter button and it will catch in less then 5 seconds. I generally don't touch the throttle at all. if it doesn't start in 4-5 seconds I might crack the throttle just a little. When it starts to get more difficult to start, I give it a tune up like I described above and it works correctly again for another 10,000 miles or so.
How soon I can take the choke off depends on the temperature.

Good Luck with your bike. I love my R60/6 it is my daily rider.

Steve Handeland
Minnesota, MN
 
I might be going out on a limb here,... but,....the post-'73 Bing mechanical slide carburetors have plunger type enrichers like Mikuni or Keihan carbs. /5's typically have the tickler buttons on the carbs that flood the throats by sinking the floats, like Amal carbs. The carbs on Kurts / pre-1970 bikes have ticklers. These type ticklers are spring loaded to quit flooding the carb when you take your fingers off.

"... I close the tickler at about 3 minutes after it starts..." says to me we are dealing with the later type carbs with the plunger style enrichers. These have the thumb lever with cables on the side of the airbox just like the 750 and 900 models. If it were my bike, I would be looking at that enricher circuit for clogged jets or deteriorated seals on the enricher mechanism. The symptoms as described sound just like what happens on a Type 64 carb when the enricher jet in the bottom of the float bowl becomes obstructed.

Mechanical Bings (Type 53's) are dismal carburetors. They are nearly impossible to correct once they go bad. A good option for 600cc bikes is the Mikuni 26mm carb conversion kit. Rocky Point cycle used to offer this kit.
 
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Thanks for the responses. It is a 1976 with the Bing slide carbs. It has the choke lever on the clam shell, not a tickler. I had the carbs rebuilt by Bing last year and paid a pretty penny so I hope they are not the problem. I will look towards the plug wires. I do get a spark from each when I lay them against the cylinder head. I had the timing and valve clearances set last year by a BMW dealer and have only ridden it 500 miles since then. From the comments it is obviously not acting like a typical air head start up so I need to examine the whole system and find the problem.
 
I have quite a bit of experience with 1975 R60/6 which I think is essentially same as yours - great smooth bike
to ride - only complaint is usually needs premium gas when worked hard rather than the cheap crap which will run an R75

You do not say just how cold is "cold" but from my experience your bike hard starting is definitely not normal

My bike in Florida in winters when we had numerous cold mornings with frost and worried citrus growers
would start almost instantly at 28-30 deg F - and drive away within 30 seconds (15w40 auto oil at that time)

Choke/enrichener lever down full for start - up to about half once started and all the way up by the time
I got to town at 45mph and 2 miles running - never needed any choke/enrichener lever use for rest of the day

Just what is wrong with your bike I cannot say but definitely not normal by my experience

Be sure of the cable adjustment on the choke enrichener. The cable pulls up a pencil diameter piston
in carb body. This piston has a soft stopper material at bottom which closes off an upward facing jet or port
when the lever is in the up or run position on the airbox. Be sure the lever action when up causes this small piston
to be pushed all the way down to stop off the enrichener port or you will never be able to tune the bike

Many people are fooled by this and it will drive you nuts. I have to assume that Bing rebuilt the carb properly
and did not dissolve away the stopper material at the bottom of this small piston as some others have - if so
a pencil eraser will work in a pinch

The way these carbs clamp up to the head makes it sometimes hard to eliminate air leaks at the carb/head interface
and these carbs like to cause the head spigot to become slightly unscrewed also making air leaks

Check for air leaks between head and carbs

As others have said - valve adjust and timing must be known to be correct before messing with carbs
 
Thanks 44006. Cold for me is about 40F this week. I will check the cable adjustment on the enricher for sure and verify valve adjustment and timing. I appreciate the info.
 
There was an article in the O.N. not very long ago where it was found that the rotating disc of the enrichener circuit (item 47 in the Bing diagram) was put in backwards; I forget if it was rotated 180 degrees (wrong face "out") or if the left & right pieces got swapped.
 
Not mentioned yet but critical is the condition of the "intake manifolds." An air (vacuum) leak between the carburetor and the cylinder will create the lean mixture it sounds like you're experiencing.

This includes tightness of clamps as well as porosity of the intake tubes themselves. If they're rubber and old, they are likely due for replacement. Also important (if applicable to this configuration) is whether the intake stubs are screwed tightly into the cylinder. Maybe even locktighted.
 
Not mentioned yet but critical is the condition of the "intake manifolds." An air (vacuum) leak between the carburetor and the cylinder will create the lean mixture it sounds like you're experiencing.

This includes tightness of clamps as well as porosity of the intake tubes themselves. If they're rubber and old, they are likely due for replacement. Also important (if applicable to this configuration) is whether the intake stubs are screwed tightly into the cylinder. Maybe even locktighted.

OK, I looked at the clamps and you were correct. They were loose and the rubber is original I believe. The cold would exacerbate the issue. Its raining outside so I am going to trickle charge the battery finish adjusting the cables and see what progress I can make. Thanks a ton lkchris.:)
 
OK, I looked at the clamps and you were correct. They were loose and the rubber is original I believe. The cold would exacerbate the issue. Its raining outside so I am going to trickle charge the battery finish adjusting the cables and see what progress I can make. Thanks a ton lkchris.:)

Wrong!!! There are no rubber bits where the carburetor fits to the intake port on a 600 in original configuration. The only rubber sleeves would be on the air filter side of the carburetors and as such would have little effect on the air/fuel mixture. These type carburetors (type 53) are fitted to the heads on a slip fit with a hardened cardboard sleeve inside the flange and a single circle clamp. This clamp compresses the flange of the intake side of the carburetor on to the cardboard sleeve and the intake stub of the head.

Additionally, there is no variable jet (rotating disc) on a 600 in original configuration as Pauls1150 suggests.

We must now ask if Wasserwolfs bike still has the original type 53 Bing mechanical slide carburetors fitted.

Now then, if Wasserwolfs bike had been retro-fitted with same year top end from a 750 or 900, it could be fitted with a pair of type 64 vacuum carburetors. A picture might be helpful.
 
Just want to verify one thing. When you try to start cold, you should be pressing the choke lever DOWN as much as you can. Once running for a minute or so the lever goes UP till it's horizontal. There's a photo of the /6 choke lever - in Clymer's I think - that is captioned backwards.
 
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